Information processor and digital plate inspection method

ABSTRACT

An information processor includes a display unit configured to display page content of each of a first page and a second page expressed in a page description language, a difference detection unit configured to detect a difference between an object included in the first page and an object included in the second page by analyzing an object structure in page description data of each of the first page and the second page and by comparing the first page and the second page which are each in a state of an object of the page description data, and a display control unit configured to control the display unit to display information on the difference detected by the difference detection unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The patent application claims priority under 35 U.S.C. §119 to JapanesePatent Application No. 2014-146579, filed on Jul. 17, 2014. Each of theabove application(s) is hereby expressly incorporated by reference, inits entirety, into the present application.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an information processor and a digitalplate inspection method, and particularly relates to an informationprocessing technology dealing with document data as an electronicmanuscript for printing.

Description of the Related Art

In recent years, a manuscript for printing is created on a computer, andtreated as electronic data (in Japanese Patent Application Laid-Open No.2009-295164 and Japanese Patent Application Laid-Open No. 2003-76996).Document data described by a page description language (PDL) has beenwidely used as a data format of the electronic manuscript for printing.An electronic document described by the PDL is referred to as a “PDLdocument”, and data of the PDL document is referred to as “PDL data”.

The PDL data is data for expressing printing content for each page onthe basis of an object including characters or images. The PDL data isvector data independent of a resolution or the like of an output devicesuch as a printer or a platesetter. The PDL data is subjected torasterization processing by a raster image processor (RIP) to beconverted into raster image data which expresses as a set of pixels anobject including characters and images constituting a page image. Theraster image data is data obtained by encoding pixels in a page into adigital format. A printer performs printing on the basis of the rasterimage data and a platesetter performs plate making on the basis of theraster image data.

SUMMARY OF THE INVENTION

The electronic manuscript for printing is usually revised or modifiedseveral times to finally bring a manuscript to completion. At stages ofan edit process, proofread process, or plate making process of themanuscript, digital plate inspection is performed for checking contentof the manuscript. The “digital plate inspection” refers to comparingtwo pages on a monitor to confirm changed portions. The digital plateinspection of related art has used the method in which the entire PDLpage is subjected to the RIP processing to compare a bitmap of a pagebefore modification with a bitmap of a page after modification.

However, the method of the digital plate inspection of related art candetect the changed portion, but has a defect in that content of changein a PDL object attribute cannot be confirmed. Examples of the “contentof change in a PDL object attribute” include those where an RGB image ischanged to a CMYK image, for example. In the method of the digital plateinspection of related art, a difference involved by changing a colorcoordinate system (color space) for the image object had been difficultto grasp.

Further, in the method of the digital plate inspection of related art,since the entire page is subjected to the RIP processing and the bitmapimage of the entire page is compared, a slight changed portion of anobject within the page is detected as a large difference in the bitmapimage in some cases. For example, in a case where insertion or deletionof the characters causes a linefeed in the character string or the liketo shift the entire character string, the whole thereof is detected as adifference of the page image. For this reason, a slight changed portionin the character string due to character insertion, character deletionor the like is hard to find out.

The above problem is not limited to the case where the pages arecompared between the page after modification and the corresponding pagebefore modification, but is the problem common to cases where twocounterpointed pages are compared to confirm a different pointregardless of whether or not there is page replacement relation involvedby modification. In the description, the term “changed portion” is usedas the term meaning a “different portion” or a “differing portion” incomparison between the pages having no anteroposterior relation ofmodification. The term “content of change” is used as the term meaning a“different point”, a “different content” or “differing content” incomparison between the pages having no anteroposterior relation ofmodification.

The present invention has been made in consideration of such acircumstance, and has an object to provide an information processor, aprogram, and a digital plate inspection method capable of resolving theproblem of the digital plate inspection of related art to confirm achanged portion in an object and content of change in an objectattribute.

In order to solve problems, aspects of the invention below are provided.

An information processor according to a first aspect is an informationprocessor, including a display unit configured to display page contentof each of a first page and a second page expressed in a pagedescription language, a difference detection unit configured to detect adifference between an object included in the first page and an objectincluded in the second by analyzing an object structure in pagedescription data of each of the first page and the second page and bycomparing the first page and the second page which are each in a stateof an object of the page description data, and a display control unitconfigured to control the display unit to display information on thedifference detected by the difference detection unit.

According to the first aspect, the comparison is performed with each thepages being in a state of an object of the page description data, whichmakes it possible to detect a changed portion (different point)concerning content of the object as well as to confirm a difference inattribute information concerning how an attribute in a state of the PDLobject is different. According to the first aspect, a slight changedportion of the object can be identified.

A second aspect may have a configuration in which, in the informationprocessor in the first aspect, the information on the differenceincludes information indicating a portion at which the difference isdetected and information indicating a different point in an objectattribute.

According to the second aspect, besides the difference concerning thecontent of the object, the content of change in the attribute can bealso confirmed.

As a third aspect, the information processor in the first aspect or thesecond aspect may have a configuration in which a display mode in whichthe display unit displays the information on the difference includes aplurality of modes that is at least two modes of a first mode in whichthe first page and the second page are arranged to be displayed, asecond mode in which the first page and the second page are toggled tobe displayed, and a third mode in which a portion of the differencebetween the first page and the second page is intensified to bedisplayed more than a portion common to the first and second pages.

As a fourth aspect, the information processor in the third aspect mayhave a configuration which includes a display mode decision unitconfigured to decide a default display mode from among plural modes, thedisplay mode decision unit deciding the default display mode from amongthe plural modes depending on a magnitude of the difference detected bythe difference detection unit.

As a fifth aspect, the information processor in any one of the firstaspect to the fourth aspect may have a configuration in which thedisplay control unit displays an icon at a portion on the object atwhich a difference is detected by the difference detection unit, andchanges a form of the icon depending on a magnitude of the differencedetected by the difference detection unit.

As a sixth aspect, the information processor in the fifth aspect mayhave a configuration in which the display control unit controls thedisplay unit to display, in concert with a user operation with respectthe icon, information indicating a different point in an attribute of anobject corresponding to the icon.

As an seventh aspect, the information processor in any one the firstaspect to the sixth aspect may have a configuration in which thedifference detection unit includes an object comparison processing unitconfigured to compare the objects for each of plural object types inunits of objects which belong to the same object type, the objects beingclassified into the plural object types used for the page descriptionlanguage.

As an eighth aspect, the information processor in the seventh aspect mayhave a configuration in which the plural object types include acharacter, an image, and a graphic.

The “character” is synonymous with a “text”. The “image” of the objecttype represents a so-called “digital photograph” and means a digitalimage having a digital signal value indicating a tone for each pixel.The “digital image” is synonymous with an “electronic image” or an“electrophotography”. The “graphic” is a category distinguished from the“image”, and refers to a line drawing or pattern created using a drawingtool or the like, or a design in combination with these and colors. The“graphic” includes a handwritten line drawing and a combination of theline drawing and coloring, the “coloring” including gradation. The term“graphic” may be replaced with the term “illustration” or “diagram”.

A configuration may be such that, in a case of comparing the graphicobjects, images of the graphic converted into a bitmap format arecompared. A configuration may be such that, of three object types of thecharacters, the image, and the graphic, the character and image objectsare compared in a state of a PDL object, and the graphic object isconverted into a bitmap graphic image and then compared.

As ninth aspect, the information processor in the seventh aspect or theeighth aspect may have a configuration which includes an operation unitconfigured to accept a user operation specifying an object type, of theplural object types, on which the information on the difference is to bedisplayed, in which the display control unit controls displaying theinformation on the difference concerning the object type specified fromthe operation unit.

According to the ninth aspect, the comparison may be performed with aviewpoint being specified such as limitation on the object type to becompared or the like.

As tenth aspect, the information processor in any one of the firstaspect to the ninth aspect may have a configuration in which the firstpage is one page having been included in the plural pages which documentdata has, and the second page is a page after modification obtained bymodifying content of the first page and is to be replaced with the firstpage and taken into the document data.

In the tenth aspect, the first page corresponds to a “page beforemodification”. The first page is a page subjected to replacement that isto be replaced with the second page by way of the page replacement.According to the tenth aspect, the page before modification and the pageafter modification can be compared on a screen of the display unit toconfirm the changed portion and the content of change in an objectattribute.

A non-transitory computer-readable medium according to an eleventhaspect is a non-transitory computer-readable medium recording a programcausing a computer to implement a display function to cause the displayunit to display page content of each of a first page and a second pageexpressed in a page description language, a difference detectionfunction to detect a difference between an object included in the firstpage and an object included in the second by analyzing an objectstructure in page description data of each of the first page and thesecond page and by comparing the first page and the second page whichare each in a state of an object of the page description data, and adisplay control function to control the display unit to displayinformation on the difference detected by the difference detection unit.

The non-transitory computer-readable medium in the eleventh aspect mayhave an adequate combination of items the same as specified items of theinformation processor specified in from the second aspect to the tenthaspect. In this case, the processing unit or function unit as a devicewhich serves as the processing and function specified in the informationprocessor can be grasped as an element of the “functions” of the programexecuting the corresponding processing and operation.

A digital plate inspection method according to a twelfth aspect is adigital plate inspection method including a display step of causing thedisplay unit to display page content of each of a first page and asecond page expressed in a page description language, a differencedetection step of detecting a difference between an object included inthe first page and an object included in the second page by analyzing anobject structure in page description data of each of the first page andthe second page and by comparing the first page and the second pagewhich are each in a state of an object of the page description data, anda display control step of controlling the display unit to displayinformation on the difference detected by the difference detection unit.

The digital plate inspection method in the twelfth aspect may have anadequate combination of items the same as specified items of theinformation processor specified in from the second aspect to the tenthaspect. In this case, the processing unit or function unit as a devicewhich serves as the processing and function specified in the informationprocessor can be grasped as an element of the “steps” of thecorresponding processing and operation.

According to the present invention, a changed portion in an object canbe easily confirmed and content of change in an object attribute can beconfirmed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a configuration of an informationprocessor according to an embodiment of the invention;

FIG. 2 is a block diagram showing a detailed configuration of an objectstructural analysis unit;

FIG. 3 is an illustration diagram showing an outline of an automaticpage replacement function attained in the embodiment;

FIG. 4 is a flowchart showing a procedure of an automatic pagereplacement method according to the embodiment of the invention;

FIG. 5 is flowchart showing content of search processing;

FIG. 6 is a flowchart showing a concrete example of the searchprocessing;

FIG. 7 is a block diagram showing a main part configuration of aninformation processor having a digital plate inspection function;

FIG. 8 is an illustration showing an exemplary GUI (Graphical UserInterface) for a comparison screen by way of a display mode of “arrangeall display”;

FIG. 9 is an illustration showing an exemplary detailed comparisonscreen regarding a character object;

FIG. 10 is an illustration showing an exemplary detailed comparisonscreen for images;

FIG. 11 is an illustration diagram of an object comparison method commonto all object types;

FIG. 12A is an illustration diagram of an example comparing content ofcharacter strings;

FIG. 12B is an illustration diagram of an example comparing appearancesof character strings; and

FIGS. 13A to 13C are illustration diagrams of a procedure for extractinga graphic area, and FIG. 13A shows an exemplary PDL page, FIG. 13B showsan exemplary image from which objects of characters and image areremoved and which is converted into a bitmap, and FIG. 13C shows anexample where the graphic area is extracted from the bitmap in FIG. 13B.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a description is given in detail of embodiments of thepresent invention with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a configuration of an informationprocessor 10 according to an embodiment of the invention. An informationprocessor 10 which is a device for processing document data as anelectronic manuscript for printing has a digital plate inspectionfunction. The information processor 10 in this example has, besides theplate inspection function, an automatic page replacement function. Here,a description is given of, as an example of a usage form of theinformation processor 10, a usage form where a difference between a“page before modification” and a “page after modification” which aresubjected page replacement by the automatic page replacement function isconfirmed by the digital plate inspection function. First, the automaticpage replacement function is described and then the digital plateinspection function is described in this order for explanation.

The information processor 10 includes a first document data storage unit12, data acquisition unit 14, second document data storage unit 16,priority setting unit 18, search unit 20, and page replacementprocessing unit 22. The information processor 10 further includes abitmap conversion unit 26, graphic area extraction unit 28, differencedetection unit 30, display control unit 32, user interface (UI) controlunit 34, operation unit 36, and display unit 38.

The information processor 10 may be achieved by combining hardware andsoftware of a computer. The term “software” is synonymous with theprogram. The “computer” includes various types of computers such as adesktop type, notebook type, or tablet type. The information processor10 can be achieved using one computer and can also be achieved using aplurality of computers to divide functions. The information processor 10may be achieved as one function of a server or may be achieved as onefunction of a client terminal.

The function of the information processor 10 can be achieved as onefunction of a DTP (Desk Top Publishing) device, or as one function of aRIP (Raster Image Processor) device. The DTP device is a device forcreating an electronic manuscript representing image content intended tobe printed. The DTP device is used for working to edit and lay out on aprinting surface various kinds of image parts such as characters,images, and graphics. The DTP device may be configured to have, besidesthe function to create the electronic manuscript, a function to edit orproofread the electronic manuscript.

The RIP device functions as a device which subjects the data of theelectronic manuscript expressed in the page description language (PDL)to the rasterization processing to convert into data of a bitmap imagefor printing. The RIP device performs processing for converting thedocument data as an electronic manuscript into data having a rasterimage format capable of being output by a printing device.

The information processor 10 can be achieved in a form of a print dataprocessing device or print management device integrating the function ofthe DTP device and the function of the RIP device, or a computer systemor the like.

The first document data storage unit 12 is a device which stores thereinfirst document data 40 as an electronic manuscript for printing. Thefirst document data 40 is the document data which has the plural pages,and is a multi-page electronic document including plural pages in onefile. The electronic document is a document including electronic data.The “document” is synonymous with the “written document”. The firstdocument data 40 is expressed in the page description language (PDL).

The first document data 40 can be externally retrieved via the dataacquisition unit 14. In case where the information processor 10 has themanuscript creating function or the manuscript edit function, the firstdocument data 40 may be those created by use of the manuscript creatingfunction or the manuscript edit function of the information processor10.

The first document data storage unit 12 may be an internal storage unitbuilt in the information processor 10 or an external storage unitcoupled to the information processor 10, or a combination of these. Theterm “coupled” is referred to as a relationship capable of transmittinginformation, and independent of whether it is contact coupling ornon-contact coupling. The term “coupling” is a term encompassing, forexample, the contact coupling between terminals corresponding to eachother, wired connection, wireless connection, optical communicationconnection, or proper combination of these. The coupling includes a formof a network connection coupled via a telecommunications line not shownin the figure.

The first document data storage unit 12 may be configured to includevarious forms of storage units such as a hard disc drive (HDD), solidstate drive (SSD), RAM (Random Access Memory), optical disk or memorycard, or proper combination of these.

The data acquisition unit 14 is an interface part capable of retrievingsecond document data 50. The second document data 50 is electronic dataof a document including at least one page after modification that is tobe replaced with a part of the plural pages in the first document data40.

For the purpose of easy explanation here, a description is given of anexample where one certain page of the plural pages in the first documentdata 40 is modified and replace. In this case, the second document data50 representing the page after modification is the document data havingonly one page. However, in implementing the invention, the seconddocument data 50 may be an electronic document file having the pluralpages. In other words, two or more pages of the plural pages in thefirst document data 40 can be replaced, and in this case, the seconddocument data 50 is a document file having two or more pages aftermodification.

The second document data 50 is expressed in the page descriptionlanguage similarly to the first document data 40. The document datadescribed by page description language is referred as “page descriptiondata” or “PDL data”. Each of one or more pages in the PDL data isreferred to as a “PDL page”. Data of the PDL page in units of pages isreferred to as “page data”.

Examples of the page description language include, for example,PostScript from Adobe Systems Incorporated. The PDF (Portable DocumentFormat) as a format for page description is a file format extended fromthe PostScript. A PDF file corresponds to a form of the document datadescribed by the page description language.

The first document data 40 may be, for example, a multi-page file typeof electronic document in the PDF. The second document data 50 can alsobe submitted in a file type of PDF.

The data acquisition unit 14 may be configured to include a data inputterminal which retrieves the second document data 50 from the externalor another signal processor within the device. As the data acquisitionunit 14, a wired or wireless communication interface part may be usedand a medium interface part for reading out and writing in an externalstorage medium such as a memory card may be used, or proper combinationof these aspects may be used. The data acquisition unit 14 may functionas a device which retrieves not only the second document data 50 butalso the first document data 40 and other various pieces of data.

The second document data storage unit 16 is a device which storestherein the second document data 50 acquired via the data acquisitionunit 14. The second document data storage unit 16 and the first documentdata storage unit 12 may be configured respectively as a separatestorage unit, or may be configured to have a storage area divided in anidentical storage unit.

The priority setting unit 18 is a device which sets priority of searchwith respect to plural object types used for the PDL data. Kinds ofobjects usable for the PDL data include four kinds, that is, characters,image, line drawing, and smooth shade. In this example, as forclassification of the object types, three kinds of classification, thatis, “characters”, “image”, and “graphic” are used. The object type of“graphic” includes a line drawing object and a smooth shade object.

The PDL page may include an object of at least one object type of threeobject types of the characters, the image, and the graphic. An object ofcharacters is referred to as a “character object”, an object of image isreferred as an “image object”, and an object of graphic is referred as a“graphic object”.

The PDL page may include page content of picture having plural objecttypes of objects combined therein. The PDL data includes objectinformation identifying the object arranged in the page and layoutinformation identifying an arrangement position of the object. Theobject information includes information on attributes of the object.

The priority setting unit 18 has a predetermined fixed priority as adefault setting (default value). For example, the priority is defined inthe default in the order that a priority for the “characters” is thehighest, followed by the “image”, the “image” followed by the “graphic”.

The priority setting can be changed by a user operation via theoperation unit 36. In other words, the operator as a user can operatethe operation unit 36 to specify the priority. The priority setting unit18 can change the priority setting in accordance with an instructionfrom the operation unit 36. The priority setting unit 18 providesinformation on the priority to the search unit 20.

The search unit 20 is a processing unit performing the search processingfor identifying the page before modification corresponding to the pageafter modification concerning the second document data 50 from among theplural pages in the first document data 40. The search unit 20determines one kind of object type used in the search processing on thebasis of the priority of search defined with respect to the pluralobject types and by analyzing an object structure of the page aftermodification included in the second document data 50.

The search unit 20 has an object type determination unit 60. The objecttype determination unit 60 includes an object structural analysis unit62 and a search object type decision unit 64. The object structuralanalysis unit 62 functions as an “analysis unit”.

The object structural analysis unit 62 is a processing unit foranalyzing the object structure of the second document data 50 that isthe PDL data. The object structural analysis unit 62 analyzes the objectincluded in the PDL page of the second document data 50 in accordancewith the priority defined by the priority setting unit 18.

The search object type decision unit 64 defines only one object type ofan object used as a search key in the search processing on the basis ofan analysis result by the object structural analysis unit 62.

The search unit 20 has an object type search processing unit 70. Theobject type search processing unit 70 performs the search processing interms of an object belonging to one kind of object type defined by thesearch object type decision unit 64. The object type search processingunit 70 includes a character object search unit 72, character objectanalogy evaluation unit 73, image object search unit 74, image objectanalogy evaluation unit 75, graphic object search unit 76, and graphicobject analogy evaluation unit 77. A combination of the character objectanalogy evaluation unit 73, the image object analogy evaluation unit 75,and the graphic object analogy evaluation unit 77 functions as “analogyevaluation unit”.

The character object search unit 72 performs processing which uses thecharacter object included in the PDL page in the second document data 50as the search key to find out the page before modification correspondingto the second document data 50 from among the plural pages in the firstdocument data 40. The number of the character object used as the searchkey may be one or more. The use of the plural character objects as thesearch keys can improve accuracy of the search.

The character object analogy evaluation unit 73 is an arithmetic unitwhich compares a character object as the search key with a characterobject included in the first document data to evaluate the analogy. Ifthe plural character objects meeting a condition on usability as thesearch key are included within the identical page in the second documentdata 50, the character object analogy evaluation unit 73 calculates theanalogy for each of these plural character objects and totally takesaccount of the analogies of the plural character objects to evaluate theanalogy of the entire page.

The character object search unit 72 finds out a page analogous to thepage after modification concerning the second document data 50 from thefirst document data 40 on the basis of an evaluation result by thecharacter object analogy evaluation unit 73 to identify the analogouspage as the “page before modification”. The “analogous page” is a pagehaving the highest analogy in the analogy evaluation.

The image object search unit 74 performs processing which uses the imageobject included in the PDL page in the second document data 50 as thesearch key to find out the page before modification corresponding to thesecond document data 50 from among the plural pages in the firstdocument data 40.

The image object analogy evaluation unit 75 is an arithmetic unit whichcompares an image object as the search key with an image object includedin a page of the first document data to evaluate the analogy. If theplural image objects meeting a condition on usability as the search keyare included within the identical page in the second document data 50,the image object analogy evaluation unit 75 calculates the analogy foreach of these image objects and totally takes account of the analogiesof the plural image objects to evaluate the analogy of the entire page.

The image object search unit 74 finds out a page analogous to the pageafter modification concerning the second document data 50 from among thefirst document data 40 on the basis of an evaluation result by the imageobject analogy evaluation unit 75 to identify the analogous page as the“page before modification”.

The graphic object search unit 76 performs processing which uses thegraphic object included in the PDL page in the second document data 50as the search key to find out the page before modification correspondingto the second document data 50 from among the plural pages in the firstdocument data 40.

The graphic object analogy evaluation unit 77 is an arithmetic unitwhich compares a graphic object as the search key with a graphic objectincluded in the first document data to evaluate the analogy.

In comparing the graphic objects, the comparison is performed after anarea of each of the graphic objects is converted into a bitmap. Thebitmap conversion unit 26 performs processing for converting the data ofthe PDL page into image data in a bitmap format. The image data in thebitmap format is referred to as “bitmap data”, and an image expressed bythe bitmap data is referred to as a “bitmap image”. The graphic areaextraction unit 28 performs processing for extracting the graphic areacorresponding to a graphic object portion from the bitmap data.

The graphic object analogy evaluation unit 77 compares the bitmap imagesof the graphic areas extracted by the graphic area extraction unit 28with each other to evaluate the analogy. The method for evaluating theanalogy between the bitmap images of the graphic areas is the same asthe method for evaluating the analogy of the image objects. If theplural graphic objects meeting a condition on usability as the searchkey are included within the identical page in the second document data50, the graphic object analogy evaluation unit 77 calculates the analogyfor each of these graphic objects and totally takes account of theanalogies of the plural graphic objects to evaluate the analogy of theentire page.

The graphic object search unit 76 finds out a page analogous to the pageafter modification concerning the second document data 50 from among thefirst document data 40 on the basis of an evaluation result by thegraphic object analogy evaluation unit 77 to identify the analogous pageas the “page before modification”.

The page replacement processing unit 22 performs page replacementprocessing for replacing the page before modification in the firstdocument data 40 identified by the search unit 20 with the page aftermodification concerning the second document data 50. The pagereplacement processing is satisfactory so long as the resultant hascontent changed into the content of the page after modification, andthus, there are included not only a case where the entire data of thepage before modification is completely rewritten with the data of thepage after modification but also a case where original data is used fora portion, in the data of the page before modification, which is commonto the data of the page after modification and a part of the datacorresponding to a difference portion as a difference concerning amodified portion is rewritten.

Once the page replacement processing is performed by the pagereplacement processing unit 22, the first document data 40 after havingbeen subjected to the page replacement processing is stored in the firstdocument data storage unit 12. The configuration may be such that, instoring the first document data 40 after having been subjected the pagereplacement processing, the first document data 40 is saved with thefile before being subjected to the page replacement being overwritten,or the file before being subjected to the page replacement is remainedand the first document data 40 after having been subjected to the pagereplacement processing is saved.

The difference detection unit 30 is a processing unit for detecting adifference between an object included in the page after modification andan object included in the page before modification by analyzing anobject structure in the page description data of each of the page aftermodification that is to be subjected to the page replacement processingby the page replacement processing unit 22 and the page beforemodification in the first document data and by comparing the pagesbefore and after modification which are each in a state of an object ofthe page description data.

The display control unit 32 controls screen displaying of the displayunit 38. In other words, the display control unit 32 performs displaycontrol for controlling the display unit 38 to display various pieces ofinformation. The display control unit 32 controls the display unit 38 todisplay information on the difference detected by the differencedetection unit 30.

The user interface (UI) control unit 34 controls input processing comingfrom the operation unit 36 and output processing output to the displayunit 38. A display device used for the display unit 38 includes a liquidcrystal display, an organic EL (Electro-Luminescence) display or thelike. The display unit 38 is a device which provides the information tothe operator through displaying on the screen. The operation unit 36 isan input device for accepting the user operation. Various input devicesmay be used for the operation unit 36 such as a keyboard, mouse, touchpanel, and trackball, and a proper combination of these may be used. Theoperator can input various pieces of information using the operationunit 36.

FIG. 2 is a block diagram showing a detailed configuration of the objectstructural analysis unit 62. The object structural analysis unit 62includes a number-of-characters threshold setting part 82,number-of-characters determination part 83, image objectnumber-of-pixels threshold setting part 84, image objectnumber-of-pixels determination part 85, graphic area number-of-pixelsthreshold setting part 86, graphic area number-of-pixels determinationpart 87, bitmap conversion part 88, and graphic area extraction part 89.

The number-of-characters threshold setting part 82 sets a thresholdregarding the number of characters that is a criterion for determiningwhether or not the search is performed on the basis of the characters.The threshold regarding the number of characters is referred to as a“number-of-characters threshold”. The number-of-characters threshold isa value defining a lower limit on the number of characters of thecharacter string which can be used for the search on the basis of thecharacter object. In other words, the character object meeting acondition where the number of characters thereof is equal to or morethan the number-of-characters threshold can be used as the search key.The number-of-characters threshold corresponds to a “first threshold”.

The number-of-characters threshold has a default setting value definedin advance by a program. Instead of or in combination with setting thenumber-of-characters threshold by way of such a default setting value,the number-of-characters threshold can be set to a desired value orchanged on the basis of the user operation coming from the operationunit 36.

The number-of-characters determination part 83 determines whether or notthere exists the character object having the character string equal toor more than the number-of-characters threshold in the page aftermodification.

The image object number-of-pixels threshold setting part 84 sets athreshold regarding the number of pixels that is a criterion fordetermining whether or not the search is performed on the basis of theimage. The threshold regarding the number of pixels of the image objectis referred to as an “image object number-of-pixels threshold”. Theimage object number-of-pixels threshold is a value defining a lowerlimit on the number of pixels of the image object required when thesearch on the basis of the image object is performed. In other words,the image object meeting a condition where the number of pixels thereofis equal to or more than the image object number-of-pixels threshold canbe used as the search key. The image object number-of-pixels thresholdcorresponds to a “second threshold”.

The image object number-of-pixels threshold has a default setting valuedefined in advance by a program. Instead of or in combination withsetting the image object number-of-pixels threshold by way of such adefault setting value, the image object number-of-pixels threshold canbe set to a desired value or changed on the basis of the user operationcoming from the operation unit 36.

The image object number-of-pixels determination part 85 determineswhether or not there exists the image object having the number of pixelsequal to or more than the image object number-of-pixels threshold in thepage after modification.

The graphic area number-of-pixels threshold setting part 86 sets athreshold regarding the number of pixels that is a criterion fordetermining whether or not the search is performed on the basis of thegraphic. The threshold regarding the number of pixels in the graphicarea is referred to as a “graphic area number-of-pixels threshold”. Thegraphic area number-of-pixels threshold is a value defining a lowerlimit on the number of pixels in the graphic area required when thesearch on the basis of the graphic is performed. In other words, thegraphic object meeting a condition where the number of pixels thereof isequal to or more than the graphic area number-of-pixels threshold can beused as the search key.

The graphic area number-of-pixels threshold has a default setting valuedefined in advance by a program. Instead of or in combination withsetting the graphic area number-of-pixels threshold by way of such adefault setting value, the graphic area number-of-pixels threshold canbe set to a desired value or changed on the basis of the user operationcoming from the operation unit 36.

The graphic area number-of-pixels determination part 87 determineswhether or not there exists the graphic area having the number of pixelsequal to or more than the graphic area number-of-pixels threshold in thepage after modification.

The bitmap conversion part 88 performs processing for converting the PDLdata of the page after modification into the image data in the bitmapformat. The graphic area extraction part 89 performs processing forextracting the graphic area that is a bitmap area corresponding to partof the graphic object from the bitmap data generated by the bitmapconversion part 88.

The bitmap conversion part 88 and the graphic area extraction part 89shown in FIG. 2 may be respectively the same as the bitmap conversionunit 26 and graphic area extraction unit 28 illustrated in FIG. 1, orthe identical configurations may be used between them respectively. Acombination of the bitmap conversion unit 26 and the graphic areaextraction unit 28, and a combination of the bitmap conversion part 88and the graphic area extraction part 89 function to create a bitmap ofan area containing at least the graphic object from the page of thedocument data of at least one of the first document data 40 and thesecond document data 50, and extract the bitmap area corresponding tothe graphic object.

The object structural analysis unit 62 shown in FIG. 2 performs thedeterminations step by step by the number-of-characters determinationpart 83, the image object number-of-pixels determination part 85, andthe graphic area number-of-pixels determination part 87 in accordancewith the priority defined by the priority setting unit 18 illustrated inFIG. 1.

For example, in a case where the priority is defined in the order ofcharacters, image, and graphic in descending order of the priority ofsearch, first, the number-of-characters determination part 83 determineswhether or not there exits the character object having the characterstring equal to or more than the number-of-characters threshold that isthe first threshold. If the character object having the character stringequal to or more than the number-of-characters threshold exists in thepage after modification, the number-of-characters determination part 83notifies the search object type decision unit 64 (see FIG. 1) ofdetermination information indicating that there exits the characterobject meeting the condition of the character string equal to or morethan the number-of-characters threshold. The search object type decisionunit 64 determines a “character” object type as a kind of object typeused for the search on the basis of the determination informationobtained from the number-of-characters determination part 83. In thiscase, determination processing on the image and the graphic which arelower in the priority than the characters may be omitted, thedetermination processing on the image and the graphic being made by theimage object number-of-pixels determination part 85 and the graphic areanumber-of-pixels determination part 87, respectively.

If the character object having the character string equal to or morethan the number-of-characters threshold does not exist in the page aftermodification, the image object number-of-pixels determination part 85determines whether or not there exists the image object having thenumber of pixels equal to or more than the image object number-of-pixelsthreshold that is the second threshold. If the image object having thenumber of pixels equal to or more than the image object number-of-pixelsthreshold exists in the page after modification, the image objectnumber-of-pixels determination part 85 notifies the search object typedecision unit 64 (see FIG. 1) of determination information indicatingthat there exists the image object meeting the condition of the numberof pixels equal to or more than the image object number-of-pixelsthreshold. The search object type decision unit 64 determines an “image”object type as a kind of object type used for the search on the basis ofthe determination information obtained from the image objectnumber-of-pixels determination part 85. In this case, the determinationprocessing on the graphic which is lower in the priority than the imagemay be omitted, the determination processing on the graphic being madeby the graphic area number-of-pixels determination part 87.

If the character object having the character string equal to or morethan the number-of-characters threshold does not exist and the imageobject having the number of pixels equal to or more than the imageobject number-of-pixels threshold does not exist in the page aftermodification, the search by way of the graphic is inevitably performed.

Therefore, in a case where the priority for the graphic is set to thelowest order, the determination processing by the graphic areanumber-of-pixels determination part 87 can be omitted. In a case of aconfiguration where the priority for the graphic is fixed to the lowestorder, the graphic area number-of-pixels threshold setting part 86 andthe graphic area number-of-pixels determination part 87 may be omittedin the configuration.

[Automatic Page Replacement Function]

FIG. 3 is an illustration diagram showing an outline of an automaticpage replacement function attained in the embodiment. The “pagereplacement” refers to that a part of pages of the electronic document(written document) having plural pages is modified and replaced in unitsof pages.

In the embodiment, submitted is an electronic document representingcontent of a page 52 after modification concerning a page 42 that is onepage in the electronic document before being subjected to the pagereplacement. The “electronic document before being subjected to the pagereplacement” corresponds to the first document data 40 illustrated inFIG. 1, and is stored in the first document data storage unit 12. The“page 52 after modification” shown in FIG. 3 corresponds to the seconddocument data 50 illustrated in FIG. 1.

In FIG. 3, the page 52 after modification is illustrated as anelectronic document obtained by modifying the content of the second page(page number=2) that is the page 42 in the electronic document beforebeing subjected to the page replacement. The page 42, the second page,corresponds to the “page before modification”. The operator submits theelectronic document of the page 52 after modification without specifyinga replace destination page.

Once the page 52 after modification is submitted, a page beforemodification (here, the page 42 that is the second page) correspondingto the page 52 after modification is automatically recognized from amongthe electronic document before being subjected to the page replacementand the processing is performed for replacing the page beforemodification (reference numeral 42) with the page 52 after modification.

A function to automatically recognize the page before modification 42corresponding to the submitted page 52 after modification to replace thepages is an “automatic page replacement function”.

FIG. 4 is a flowchart showing a procedure of the automatic pagereplacement method according to the embodiment of the invention. Eachstep from step S12 to step S18 shown in FIG. 4 is implemented throughthe processing performed by the information processor 10 (see FIG. 1).

First, the first document data 40 having the plural pages is stored inthe first document data storage unit 12 (at step S12 in FIG. 4).

Subsequently, the information processor 10 (see FIG. 1) acquires thesecond document data 50 including the page after modification (at stepS14 in FIG. 4).

Next, the search unit 20 (see FIG. 1) performs the search processing foridentifying from the first document data 40 the page before modificationcorresponding to the page after modification (at step S16 in FIG. 4).

Next, the page replacement processing unit 22 (see FIG. 1) performs thepage replacement processing for replacing the page before modificationin the first document data 40 which is identified in the search step(step S16 in FIG. 4) with the page after modification (at step S18 inFIG. 4). The order of step S12 and step S14 in FIG. 4 may be inversed.

FIG. 5 is a flowchart showing content of the search processing shown atstep S16 in FIG. 4.

As shown in FIG. 5, the search processing includes a step of identifyingthe priority of search with respect the object type (step S22), a stepof analyzing the object structure of the page after modification (stepS24), a step of determining one kind of object type used for the searchprocessing from among the plural object types (step S26), and step ofsearching by use of an object belonging to the determined one kind ofobject type (step S28).

Step S22 is performed in accordance with the priority setting set by thepriority setting unit 18 illustrated in FIG. 1. Step S24 in FIG. 5 isperformed by the object structural analysis unit 62 illustrated in FIG.1 and FIG. 2. Determined is whether or not there exists an objectmeeting a condition on usability as the search key in the page aftermodification, in descending order of high priority object type inaccordance with the defined priority of search.

At step S26 in FIG. 5, one kind of object type used for the searchprocessing is determined on the basis of the analysis result from stepS24.

At step S28, searching is performed using as the search key an objectbelonging to one kind of object type determined at step S26.

FIG. 6 is a flowchart showing a concrete example of the searchprocessing. Here, a description is given of a case where the priority ofsearch is defined in the order of characters, image, and graphic, as anexample.

First, determined is whether or not there exists the character objectincluding characters the number of which is equal to or more than thefirst threshold in the submitted page after modification (step S32). Ifthe object of the character string having characters the number of whichis equal to or more than the first threshold exists in the page aftermodification, Yes determination results at step S32 and the search byuse of the character is performed (step S33).

The search step by use of the characters (step S33) performs processingfor finding out the analogous page including a character objectanalogous to the character object as the search key from among theplural pages in the first document data 40, using as the search key thecharacter object of the character string having characters the number ofwhich is equal to or more than the first threshold. The “analogous page”referred here is identified as the “page before modification”corresponding to the page after modification.

The determination of the analogy only on the object of the characterstring having characters the number of which is equal to or more thanthe first threshold allows search assurance to be improved.

The search by use of the character can determine the analogy in a highspeed and accurately as compared with the search by use of the image andthe search by use of the graphic. Therefore, as for the prioritysetting, it is preferable that the priority of search by use of thecharacter is set to the highest.

If at step S32, the object of the character string having characters thenumber of which is equal to or more than the first threshold does notexist in the page after modification, No determination results at stepS32 and the process proceeds to step S34.

At step S34, determined is whether or not there exists the image objecthaving pixels the number of which is equal to or more than the secondthreshold in the page after modification. If the image object havingpixels the number of which is equal to or more than the second thresholdexists in page after modification, Yes determination results at stepS34, and the search by use of the image is performed (step S35).

The step of the search by use of the image (step S35) performsprocessing for finding out the analogous page including an image objectanalogous to the image object as the search key from among the pluralpages in the first document data 40, using as the search key the imageobject having pixels the number of which is equal to or more than thesecond threshold.

The determination of the analogy only on the image object having pixelsthe number of which is equal to or more than the second threshold allowsthe analogy to be accurately determined.

If at step S34, the image object having pixels the number of which isequal to or more than the second threshold does not exist in page aftermodification, No determination results at step S34 and the processproceeds to step S37.

Step S37 performs the search by use of the graphic. The search by use ofthe graphic (step S37) converts a portion of the graphic object intoimage data in the bitmap format, that is, makes it into an image by wayof the RIP, and then determines the analogy as a bitmap image.

The search by use of the graphic requires the RIP processing to take aprocessing time more than the search by use of the character (step S33)and the search by use of the image (step S35). Therefore, it ispreferable that the priority of the search by use of the graphic is setto be lower than the search by use of the image.

[Digital Plate Inspection Function]

Next, a description is given of a digital plate inspection function inthe information processor 10.

FIG. 7 is a block diagram showing a main part configuration of theinformation processor 10 having the digital plate inspection function.Elements in FIG. 7 the same as those illustrated in FIG. 1 aredesignated by the same reference numerals, and the description thereofis omitted.

The difference detection unit 30 includes a character object comparisonprocessing part 92, image object comparison processing part 94, andgraphic object comparison processing part 96. The information processor10 includes a display mode decision unit 98.

The difference detection unit 30 performs processing for retrieving dataof the page before modification 102 from the first document data storageunit 12 and retrieving data of the page after modification 104 from thesecond document data storage unit 16, and then comparing both pages todetect a difference between both pages. The page before modification 102corresponds to a form of a “first page”, and the page after modification104 corresponds to a form of a “second page”.

The difference detection unit 30 can analyze the object structures inthe pages and determine whether or not a difference exists for everyobjects included in the pages to create information on the differencefor each object. A function to create the information on the differencefor each object by the difference detection unit 30 corresponds to aform of a “difference detection function”, and a step of creating theinformation on the difference for each object by the differencedetection unit 30 corresponds to a form of a “difference detectionstep”.

The character object comparison processing part 92 compares the pagebefore modification 102 with the page after modification 104 with thepages being in a state of the PDL object to create character objectdifference information 112. The character object difference information112 is information indicating a difference, that is a different point,between the character object included in the page before modification102 and the character object included in the page after modification104. The character object difference information 112 may includeinformation indicating difference in content of the character string,information indicating difference in appearance, and informationindicating difference in the attribute such as a font. The informationindicating difference in content of the character string, and theinformation indicating difference in appearance correspond to a form of“information indicating difference point”.

The image object comparison processing part 94 compares the page beforemodification 102 with the page after modification 104 with the pagesbeing in a state of the PDL object to create image object differenceinformation 114. The image object difference information 114 isinformation indicating a difference, that is a different point, betweenthe image object included in the page before modification 102 and theimage object included in the page after modification 104. The imageobject difference information 114 may include information indicatingdifference in content of the image, and information indicatingdifference in the attribute such as an image size. The attribute ofimage may include, besides the image size, resolution, compressionmethod, color space, and the like. The information indicating differencein content of the image corresponds to a form of the “informationindicating difference point”.

The graphic object comparison processing part 96 compares the pagebefore modification 102 with the page after modification 104 to creategraphic object difference information 116. In comparing the graphicobjects, data converted into the bitmap image is compared.

Picking up the object information for the object types of character,image and graphic in units of objects from the PDL data by thedifference detection unit 30 corresponds to a form of “analyzing anobject structure”. The character object comparison processing part 92,the image object comparison processing part 94, and graphic objectcomparison processing part 96 each correspond to a form of an “objectcomparison processing unit”. The character object comparison processingpart 92 and the image object comparison processing part 94 correspond toa processing unit for comparing the objects in a state of a PDL object.

The display mode decision unit 98 specifies a display mode fordisplaying the page before modification 102 and the page aftermodification 104 on the screen of the display unit 38 in the digitalplate inspection function. The information processor 10 in this examplehas three display modes an “arrange all display”, “toggle display”, and“differential intensified display” as the display mode for the digitalplate inspection.

The “arrange all display” mode is a display form where both the pageafter modification 104 and the page before modification 102 are arrangedon one screen at a time to be displayed. The “toggle display” mode is adisplay form where the page after modification 104 and the page beforemodification 102 are alternately toggled to be displayed. The display inthe “toggle display” mode is toggled automatically or in concert withthe user operation. In a case where two pages are automatically toggledand displayed, it is preferable for the user to arbitrarily specify orselect setting for a time interval of display toggling.

The “differential intensified display” mode is a display form where adifferential between the page after modification 104 and the page beforemodification 102 is visually intensified to be displayed more than aportion common to the pages 104 and 102. A “differential” is synonymouswith a “difference”. As a method of the intensified display, forexample, highlighted display, blinked display or enlarged display, or aproper combination to these may be used.

The “arrange all display” mode corresponds to a “first mode”, the“toggle display” mode corresponds to a “second mode”, and the“differential intensified display” mode corresponds to a “third mode”.The display mode may include at least one kind of mode, but preferablyis configured to have a plurality of display modes including at leasttwo display modes selected from above three kinds of mode.

The display mode decision unit 98 can set the display mode in accordancewith the user operation from the operation unit 36. The display modedecision unit 98 performs processing for automatically decide a defaultdisplay mode from among three kinds of display mode. The default displaymode is automatically changed depending on a magnitude of thedifferential between two compared pages. For example, in a case wherethe differential between two pages is large to an extent where differentpoints between the pages is relatively easy to grasp, the “arrange alldisplay” mode is set. In a case where the differential between two pagesis small to an extent where different points between the pages is hardto see at first glance, the “differential intensified display” mode isset. The default display mode decided by the display mode decision unit98 can be changed by the user operation from the operation unit 36.

The display control unit 32 controls the display unit 38 to display theinformation on the difference obtained by the difference detection unit30. A function of display control by the display control unit 32corresponds to a form of a “display control function”. A step ofcontrolling display of the display unit 38 by the display control unit32 corresponds to a form of a “display control step”. A function todisplay on the display unit 38 corresponds to a form of a “displayfunction”, and a step of displaying on the display unit 38 on the basisof the control by the display control unit 32 corresponds to a form of a“display step”. The digital plate inspection implemented by the digitalplate inspection function of the information processor 10 corresponds toa form of a “digital plate inspection method”.

FIG. 8 is an exemplary GUI (Graphical User Interface) of a comparisonscreen in the display mode “arrange all display”. A display window 120includes a display mode selection field 122, character object typespecifying button 124, image object type specifying button 126, andgraphic object type specifying button 128. The term “button” means a GUIbutton. Actions expressed by “press” with respect to the GUI buttoninclude an action for inputting an instruction corresponding to thebutton such as clicking, touching, or mousing over.

The display mode selection field 122 includes a mode type display box130 and a pull-down button 132. The mode type display box 130 is adisplay field that displays mode type information indicating the kind ofdisplay mode currently selected. The pull-down button 132 is a buttonfor displaying available choices for the display mode. When thepull-down button 132 is pressed, a pull-down menu (not shown) containingthe available choices for the display mode is displayed. The operatorcan perform an operation selecting the display mode from the pull-downmenu to change the display mode.

In the case of the display mode “arrange all display”, as shown in FIG.8, print image content of the page before modification 102 and printimage content of the page after modification 104 are arranged on thescreen at a time to be displayed. In FIG. 8, a left area in the displaywindow 120 is a page-before-modification display area 142 that displaysthe image of the page before modification 102, and a right area is apage-after-modification display area 144 that displays the image of thepage after modification 104. The page-before-modification display area142 and the page-after-modification display area 144 may be displayed ina form of being replaced with each other in terms of right and leftpositions thereof. The page before modification 102 and the page aftermodification 104 may also be displayed in a form of being verticallyarranged.

When the page after modification 104 is compared with the page beforemodification 102, if differences between the objects are detected, icons152, 154, and 156 are displayed at sites on the objects where thedifferences are found. Once any of the icons 152, 154, and 156 ispressed, detailed display is performed where detailed information on thedifference (differential) is displayed.

The display form of each of the icons 152, 154, and 156 is changeddepending on the magnitude of the difference (differential) of theobject. Examples of the icon display form changed include an aspectwhere a color of the icon is changed, or an aspect where the designitself of the icon is changed, or a combination of these. For example,an aspect may be used in which the color of the icon is switched over to“blue”, “yellow”, and “red” depending on a degree of the differential.There is an aspect where the “blue” icon is displayed at the changedportion having a relatively small differential, the “red” icon isdisplayed at the changed portion having a relatively large differential,and the “yellow” icon is displayed at the changed portion having amiddle level differential. In contrast, since the smaller thedifferential, the harder to see the difference point, the “red” icon asintensifying color for alerting the operator is displayed at the changedportion having the small differential.

The character object type specifying button 124, the image object typespecifying button 126, and the graphic object type specifying button 128each are a GUI button for specifying the viewpoint for the object typeto be compared. The character object type specifying button 124 is abutton operated when the comparison is performed with the viewpointbeing limited to the character object. Once the character object typespecifying button 124 is pressed, the comparison of only the characterobject is enabled.

The image object type specifying button 126 is a button operated whenthe comparison is performed with the viewpoint being limited to theimage object. Once the image object type specifying button 126 ispressed, the comparison of only the image object is enabled.

The graphic object type specifying button 128 is a button operated whenthe comparison is performed with the viewpoint being limited to thegraphic object. Once the graphic object type specifying button 128 ispressed, the comparison of only the graphic object is enabled.

FIG. 9 is an exemplary detailed comparison screen regarding thecharacter object. When the icon 152 illustrated in FIG. 8 is clicked ormoused over, a character detailed comparison window 160 is displayed asa screen that displays the detailed information on the differentialregarding the character object corresponding to the icon 152 as shown inFIG. 9.

The character detailed comparison window 160 includes a characterstring-before-modification display area 162, characterstring-after-modification display area 164, and attribute comparisondisplay area 166. The character string-before-modification display area162 is a display field that displays the character string of thecharacter object included in the page before modification 102 (see FIG.8). The character string-after-modification display area 164 is adisplay field that displays the character string of the character objectincluded in the page after modification 104 (see FIG. 8). In thisexample, the character string-before-modification display area 162 andthe character string-after-modification display area 164 are verticallyarranged. However, an aspect may be used in which the characterstring-before-modification display area 162 and the characterstring-after-modification display area 164 are displayed in a form ofbeing replaced with each other in terms of up and down positionsthereof, or are horizontally arranged.

The character string before modification displayed in the characterstring-before-modification display area 162 and the character stringafter modification displayed in the character string-after-modificationdisplay area 164 are compared to each other, and a different portion inthe character string, that is, a portion of the difference, ishighlighted to be displayed. The highlighted display intensifies thedifferent point to allow the operator to be alerted.

The attribute comparison display area 166 is an area that displaysinformation on a difference in a character type between beforemodification and after modification in a compared fashion. As thedifference in the character type, information on a font name and a fontsize is displayed here. As other information on the difference in thecharacter type, at least one piece of information on a color of thecharacter, bold type, and italic type can be displayed, not shown inFIG. 9.

The comparison display like this by the character detailed comparisonwindow 160 facilitates that the operator confirms the different pointbetween the character objects before and after modification.

FIG. 10 is an exemplary detailed comparison screen for the images. Whenthe icon 154 illustrated in FIG. 8 is clicked or moused over, an imagedetailed comparison window 170 is displayed as a screen that displaysthe detailed information on the differential regarding the image objectcorresponding to the icon 154 as shown in FIG. 10.

The image detailed comparison window 170 includes animage-before-modification display area 172, image-after-modificationdisplay area 174, attribute comparison display area 176, and warningdisplay area 178.

The image-before-modification display area 172 is a display field thatdisplays the image object included in the page before modification 102(see FIG. 8). The image-after-modification display area 174 is a displayfield that displays the image object included in the page aftermodification 104 (see FIG. 8). In this example, theimage-before-modification display area 172 and theimage-after-modification display area 174 are horizontally arranged.However, an aspect may be used in which the image-before-modificationdisplay area 172 and the image-after-modification display area 174 aredisplayed in a form of being replaced with each other in terms of rightand left positions thereof, or are vertically arranged.

The attribute comparison display area 176 is an area that displaysinformation on a difference in the attribute of the image object betweenbefore modification and after modification in a compared fashion. As thedifference in the attribute of the image object, information of an imageformat, the resolution, and the color coordinate system is displayedhere.

The warning display area 178 is a display field that displays messagesfor alerting the operator.

The comparison display like this by the image detailed comparison window170 facilitates that the operator confirms the different point betweenthe image objects before and after modification.

FIG. 10 is the exemplary detailed comparison display for the imageobject, but detailed comparison display for the graphic object can bealso performed using the same detailed comparison display as in FIG. 10.

According to the embodiment, in addition to detection of the changedportion in the object, how the attribute in a state of the PDL object ischanged can be confirmed. Even when a slight change such as insertion ordeletion of the characters causes entirely shift, only a portionactually changed can be detected. Further, according to the embodiment,the comparison can be performed with a viewpoint for the object typebeing specified. For example, the comparison may be made with the objecttype being limited, such as comparison of only the characters, orcomparison of only the images.

[Object Comparison Method]

Here, a description is given of an object comparison method. In the caseof searching the “page before modification” corresponding to the pageafter modification concerning the second document data 50 from among theplural pages in the first document data 40 (see FIG. 1), the objects iscompared according to rules 1 and 2 shown below to find out theanalogous page.

[Rule 1] Between two pages compared with each other, objects locatedwithin the pages are compared which are of the same object type and havecoordinates the closest to each other to calculate the analogy betweenthe objects.

[Rule 2] Concerning one of two PDL pages compared with each other, whichhas the larger number of the objects of the same object type, theanalogy is calculated for all objects of the same object type accordingto the rule 1 and a value of a sum of the respective calculatedanalogies of the objects is set to the analogy of the entire page.

A concrete example shown in FIG. 11 is used to describe the comparisonmethod on the basis of the rule 1 and the rule 2. A page [1] shown onthe left side and a page [2] shown on the right side in FIG. 11 are twopages compared with each other.

It may be construed that the page [1] is the page included in the firstdocument data 40 and the page [2] is the page included in the seconddocument data 50, and, in contrast, it may be construed that the page[1] is the page included in the second document data 50 and the page [2]is the page included in the first document data 40.

The page [1] has four objects designated by A, B, C, and D. The page [2]has three object designated by E, F, and G. For the purpose of thesimple explanation here, assume that all the objects designated by thereference characters A to G belong to the same object type. For example,assume that all the objects designated by the reference characters A toG are the “characters” object. Assume that each of the objectsdesignated by the reference characters A to G meets the condition thatthe value of the object is equal to or more than the“number-of-characters threshold”, the “image object number-of-pixelsthreshold”, or the “graphic area number-of-pixels threshold” definedcorresponding to the object type.

In paying attention to the object A located in the page [1], the object,of the objects E to G located in the page [2], which is of the sameobject type and the closest to the coordinates of the object A in thepage [1] is the object E. The coordinates of the object on the pagerepresent the arrangement position of the object.

A combination of the object A and the object E corresponds to theobjects which are of the same object type and have coordinates theclosest to each other in each page.

Similarly, a combination of the object B and the object E, a combinationof the object C and the object F, and a combination of the object D andthe object G each correspond to the objects which are of the same objecttype and have coordinates the closest to each other in each page.

According to the rule 1, the object A and the object E are compared witheach other to calculate an analogy S_(AE).

According to the rule 2, similarly, the object B and the object E arecompared with each other to calculate an analogy S_(BE), the object Cand the object F are compared with each other to calculate an analogyS_(CF), and the object D and the object G are compared with each otherto calculate an analogy S_(DG).

Then, these calculated analogies a value of a sum of S_(AE), S_(BE),S_(CF), and S_(DG), that is, “S_(AE)+S_(BE)+S_(CF)+S_(DG) ^(”) is set tothe analogy of the entire page. If the analogy of the entire page isrepresented by S_(P), “S_(P)=S_(AE)+S_(BE)+S_(CF)+S_(DG)”.

The same goes for a case where all the objects designated by thereference characters A to G are the “image” objects, or the “graphic”objects.

[Comparison Method for Each Object Type]

Next, a description is given of the comparison method for each objecttype.

<Comparison Method for Character String>

The comparison method for the character string includes comparison ofcontent of the character string and comparison of appearance of thecharacter string.

The comparison of content of the character string refers to comparing adegree to which the character string itself is changed. FIG. 12A isshown as an example. In comparing a character string “ABCDE” shown onthe left side and a character string “ABDCE” shown on the right side inFIG. 12A with each other, a portion “CD” as a part of the characterstring on the left side is changed into “DC” in the character string onthe right side. In this way, comparing the degree to which the characterstring itself is changed is the “comparison of content of the characterstring”.

In the case of comparing the content of the character string, as amethod for evaluating the analogies of two character strings to becompared, for example, a general analogy evaluation index represented bythe Levenshtein distance, or the Jaro-Winkler distance can be used.

By way of the Levenshtein distance, the number of times of each ofinsertion, deletion, and substitution of character is calculated as a“distance” between two character strings.

For example, two character strings compared, “Kitten” and “Sitting”, areused as an example to give a description. In order to obtain thecharacter string “Sitting” from the character string “Kitten”, thefollowing operation is required.

[1] “K” is substituted with “S”→Sitten

[2] “e” is substituted with “i”→Sittin

[3] “g” is inserted→Sitting

Therefore, the Levenshtein distance is “3”. Note that the operations ofinsertion, deletion, and substitution may be weighted, and the“distance” in a state of being weighted may be calculated. TheDamerau-Levenshtein distance may be used which takes into account “thenumber of times of rearrangement” as well as three operations ofinsertion, deletion, and substitution.

On the other hand, the comparison of appearance of the character stringrefers to comparing a degree to which the character string is changed interms of a font, character size, bold type, or attached line, or aproper combination of these. The “bold type” refers to comparing interms of whether or not the character string is made bold. The “attachedline” refers to comparing in terms of whether or not the characterstring is underlined or bordered, or in terms of line style.

FIG. 12B shows an example of “add underline”. With respect to thecharacter string “ABCDE” on the left side in FIG. 12B, the characterstring on the right side is not changed in the content of the characterstring but has an underline added. Such a change is evaluated as adifference in “appearance”.

In addition to the comparison of content of the character string, thedifference in appearance is taken into account to calculate the analogyof the character string. Elements of the appearance include a font and agraphics state. The font which is an element relating to a charactershape has classifications of Type, Font name, and Font family. Thegraphics state includes elements of color. The graphics state has aColor element and an Overprint element.

The character object has information relating to the font or graphicsstate attached as the attribute information on the object. By use of theattribute information on the object, the analogy of the character stringcan be calculated.

<Image Comparison Method>

A viewpoint of comparison of the image may include comparison of thecontent of the image, comparison of the image size, and consideration ofthe color space. The comparison of the content of the image includes“comparison of subject shape” and “comparison of color” in the images.The comparison of subject shape is performed by comparing features oftwo images. As an algorithm for extracting the features, ORB (OrientedFAST and Rotated BRIEF) can be used. The ORB has an advantage in thatchange in the image can be absorbed to some degrees, such as a scalechange, superimposed noise, rotation change, or lighting change betweenthe images. The ORB calculates after gray scale transformation withouttaking into account with of the color element. The ORB has an advantagein being robust over the scale change, that is, change of enlarging andreducing the image, robust over the noise, robust over the rotation, androbust over the lighting change. The expression “robust” means that evenif change occurs between the images, the features can be accuratelyextracted.

As an algorithm for extracting the features of the image, knownalgorithms represented by the SIFT (Scale-Invariant Feature Transform)or the SURF (Speeded Up Robust Features) can be used, besides the ORB.However, the ORB has an advantage in high speed processing and beingpatent-free as compared to the SIFT and the SURF. The informationprocessor 10 in the embodiment uses the ORB. The ORB is implemented inthe OpenCV (Open Source Computer Vision Library).

As the method of the “image comparison of color”, for example, a methodcan be used in which the image data is converted into Lab values tocompare a histogram. The Lab values are colors expressed using theCIE1976 (L*, a*, b*) color space. As an algorithm for comparing thehistogram, known methods can be used, such as a method of calculatingcorrelation of the histogram, a method of calculating intersection ofthe histogram, a method of applying Pearson's chi-square test, and amethod of calculating the Bhattacharyya distance, for example.

<Graphic Comparison Method>

The graphic objects are compared after each of the graphics is convertedinto the bitmap. The graphic comparison is performed in accordance withthe following procedures 1 to 4.

[Procedure 1] First, the character object and the image object areremoved from the PDL page.

[Procedure 2] Then, the page from which the image object and thecharacter object have been removed at Procedure 1 is entirely convertedinto the bitmap.

FIG. 13A is an example of the PDL page. A PDL page 200 shown in FIG. 13Aincludes character objects designated by reference numerals 212 and 214,an image object designated by a reference numeral 222, and graphicobjects designated by reference numerals 232 and 234.

FIG. 13B is an example of the page converted into the bitmap inProcedure 2. The character objects 212 and 214, and the image object 222are removed from the PDL page 200 shown in FIG. 13A and the entire pageis converted into the bitmap, resulting in a bitmap image 240 as shownin FIG. 13B. The bitmap image 240 includes graphic images 242 and 244respectively corresponding to the graphic objects 232 and 234 shown inFIG. 13A.

[Procedure 3] Areas of the graphic images 242 and 244 are extracted fromthe bitmap image 240 in the page obtained in Procedure 2.

FIG. 13C shows graphic areas 252 and 254 extracted from the bitmap image240 in Procedure 3. In the case of extracting the graphic areas 252 and254 from the bitmap image 240, a colored area is extracted from thebitmap image 240, for example. In extracting the colored area, it ispreferable that colored pixel areas which are even somewhat apart fromeach other are recognized as an identical clump of graphic.

[Procedure 4] The graphic areas extracted in Procedure 3 are compared asthe images.

Procedures 1 to 3 are performed by the combination of the bitmapconversion unit 26 and the graphic area extraction unit 28 illustratedin FIG. 1. Procedures 1 to 3 are performed by the combination of thebitmap conversion part 88 and the graphic area extraction part 89illustrated in FIG. 2.

Procedure 4 is performed by the graphic object search unit 76 and thegraphic object analogy evaluation unit 77 illustrated in FIG. 1.Procedures 1 to 4 are performed by the graphic object comparisonprocessing part 96 illustrated in FIG. 7.

<Program Causing Computer to Function as Information Processor>

A program, which causes a computer to function as the informationprocessor implementing the automatic page replacement function and/orthe digital plate inspection function described in the above embodiment,can be stored in a CD-ROM (Compact Disc Read-Only Memory), magneticdisk, and other computer-readable media (tangible transient informationstorage media) to provide the relevant program via the relevantinformation storage media. Instead of the aspect that the program isstored in such an information storage medium and provided, atelecommunications line such as the Internet can be also used to providea program signal as a download service.

This program installed in the computer can cause the computer toimplement the automatic page replacement function and/or the digitalplate inspection function.

An aspect may be used in which a part or all of the program forimplementing the automatic page replacement function and/or the digitalplate inspection function described in the embodiment is installed in ahost computer of a printing system, or is applied as an operationprogram for a central processing unit (CPU) of a printer or platesetteras an image output device.

<System Configuration Example>

The information processor 10 illustrated in FIG. 1 may be configuredinto an integrated device in which configurations of the respectiveunits are integrally built in one device, or may be configured into afunctionally-distributed isolated type system in which a plurality ofdevices as individual function units or processing units are combined.

For example, each of a device functioning as the first document datastorage unit 12 and a device functioning as the search unit 20 may beconfigured into a separated device. Each of the page replacementprocessing unit 22 and the difference detection unit 30 may beconfigured into a separated device.

For example, the first document data storage unit 12 and second documentdata storage unit 16 shown in FIG. 1 may be servers for data saving onthe network, and the priority setting unit 18, search unit 20, pagereplacement processing unit 22, bitmap conversion unit 26, graphic areaextraction unit 28, difference detection unit 30, display control unit32, UI control unit 34, operation unit 36, and display unit 38 may beclient terminals in a manuscript production company or a printingcompany. Alternatively, an aspect may be used in which the function ofthe search unit 20 is provided by way of a server on the network.

<Modification Example 1>

In a case where the second document data 50 includes plural pages aftermodification, each of the pages is subjected to the search processingand the page replacement processing in the same manner as the methoddescribed above.

Modification Example 2>

The digital plate inspection function described using FIG. 7 to FIG. 10may be used as a function independent of the automatic page replacementfunction. In other words, two pages compared with each other by thedigital plate inspection function may not be limited to the submittedpage after modification 104 and the page before modification 102searched for by the automatic page replacement function but may be twopages selected arbitrarily. For example, the submitted page aftermodification 104 and the page having the page number of the replacedestination which is grasped in advance may be compared to confirm thechanged portion. Of the compared two pages, one corresponds to the“first page”, and the other corresponds to the “second page”.

<Advantage of Embodiment>

In the embodiment, two pages to be compared are subjected to the digitalplate inspection with the pages being in a state of a PDL object.According to the digital plate inspection function described in theembodiment, the changed portions in the page before modification andpage after modification can be easily confirmed in units of objects, andthe content of change in the object attribute can be also confirmed.This makes it possible to efficiently check whether or not the intendedmodification is appropriately performed.

Moreover, according to the embodiment, a slight changed portion due tocharacter insertion, character deletion or the like is easy to grasp.

Furthermore, according to the embodiment, the comparison may be madewith the object type being limited, or the like, such as comparison ofonly the characters.

According to the automatic page replacement function described in theembodiment, if the second document data including the page aftermodification is only submitted even with no replace destination pagebeing specified, the page replacement is automatically performed,reducing the work burden on the operator.

For example, the electronic manuscript of a printed material havingplural pages such as a magazine, a catalog, a photo book and the like issometimes subjected to modification only for a part of the pages and themodified pages are replaced in units of pages at a stage in an editwork, a proofread work or the like. In a manuscript submission system ofrelated art, when the page replacement is performed, the operator hasneeded to specify a page number of the replace destination that is to bereplaced, from among the plural pages in the electronic manuscript. Whenthe operator specifies the page number of a replace destination page,content of the specified replace destination page is processed to bereplaced with a replacement page that is a page after modification whichis newly submitted. The “replace destination page” is a page subjectedto replacement that is to be replaced, and is the “page beforemodification”. The “replacement page” is the “page after modification”having changed content of the page subjected to replacement.

However, if the operator does not grasp the page number of the replacedestination, he/she has to found out the page of the replace destinationfrom among the plural pages. It bears a great work burden and takes timefor the operator to find out the page of the replace destination whileconfirming the content of the respective plural pages.

Division of labor has proceeded in the printing industry, where aplurality of persons are often engaged in edit, confirmation, and thelike of the manuscript, such as a planning company (i.e., client of theprinted material) to plan the printed material, a designer or staff inthe manuscript production company, a staff in the printing company, andthe like. For this reason, a creator creating the modified page and anoperator performing the page replacement work and confirmation are notnecessarily the identical person. In a case where only the document dataof the modified page is submitted, the operator cannot grasp the replacedestination page in some cases.

Even in a case where the page number of the replace destination isknown, operations of at least three stages shown below are required,resulting in a great burden on the operator, which is inefficient.

[1] Specifying page number, [2] Confirming replace destination page, [3]Selecting replacement page.

In this regard, according to the embodiment, the page beforemodification corresponding to the submitted page after modification isautomatically searched for to perform the page replacement, improvingthe work efficiency.

According to the embodiment, the difference between the page beforemodification and the page after modification which are to be subjectedto the page replacement can be confirmed by the digital plate inspectionfunction.

Constituent features in the embodiment of the present inventiondescribed hereinabove may be adequately changed, added and deletedwithin a range not departing from the scope of the invention. Theinvention is not limited to the above described embodiment and manymodifications may be made by a person ordinarily skilled in the artwithin the technical idea of the invention.

What is claimed is:
 1. An information processing device, comprising: adisplay configured to display page content of each of a first page and asecond page expressed in a page description language; and a processorconfigured to perform operations of: a difference detection unitconfigured to detect a difference between an object included in thefirst page and an object included in the second page by analyzing anobject structure in page description data of each of the first page andthe second page and by comparing the first page and the second pagewhich are each in a state of an object of the page description data; anda display control unit configured to control the display to displayinformation on the difference detected by the difference detection unit,wherein the difference detection unit includes an object comparisonprocessing unit configured to compare simultaneously the objects foreach of plural object types in units of objects which belong to the sameobject type, the objects being classified into the plural object typesused for the page description language; said processor furtherconfigured to perform operations of an operation unit configured toaccept a user operation specifying an object type, of the plural objecttypes, on which information on the difference is to be displayed,wherein the display control unit controls displaying the information onthe difference concerning the object type specified from the operationunit.
 2. The information processing device according to claim 1, whereinthe information on the difference includes information indicating aportion at which the difference is detected and information indicating adifferent point in an object attribute.
 3. The information processingdevice according to claim 1, wherein a display mode in which the displaydisplays the information on the difference includes a plurality of modesthat is at least two modes of a first mode in which the first page andthe second page are arranged to be displayed, a second mode in which thefirst page and the second page are toggled to be displayed, and a thirdmode in which a difference between the first page and the second page isintensified to be displayed more than a portion common to the first andsecond pages.
 4. The information processing device according to claim 3,wherein the processor is further configured to perform operations of adisplay mode decision unit to decide a default display mode from amongplural modes, the display mode decision unit deciding the defaultdisplay mode from among the plural modes depending on a magnitude of thedifference detected by the difference detection unit.
 5. The informationprocessing device according to claim 1, wherein the display control unitdisplays an icon at a portion on the object at which a difference isdetected by the difference detection unit, and changes a form of theicon depending on a magnitude of the difference detected by thedifference detection unit.
 6. The information processing deviceaccording to claim 5, wherein the display control unit controls thedisplay to display, in concert with a user operation with respect to theicon, information indicating a different point in an attribute of anobject corresponding to the icon.
 7. The information processing deviceaccording to claim 1, wherein the plural object types include acharacter, an image and a graphic.
 8. The information processing deviceaccording to claim 1, wherein the first page is one page having beenincluded in plural pages which document data has, and the second page isa page after modification obtained by modifying content of the firstpage and is to be replaced with the first page and taken into thedocument data.
 9. A non-transitory computer-readable medium recording aprogram causing a computer to implement: a display function to cause adisplay to display page content of each of a first page and a secondpage expressed in a page description language; a difference detectionfunction to detect a difference between an object included in the firstpage and an object included in the second page by analyzing an objectstructure in page description data of each of the first page and thesecond page and by comparing the first page and the second page whichare each in a state of an object of the page description data; and adisplay control function to control the display to display informationon the difference detected by the difference detection function, whereinin implementing the difference detection function, the computer furtherperforms an object comparison processing function to comparesimultaneously the objects for each of plural object types in units ofobjects which belong to the same object type, the objects beingclassified into the plural object types used for the page descriptionlanguage; said computer further configured to perform operations of anoperation unit configured to accept a user operation specifying anobject type, of the plural object types, on which information on thedifference is to be displayed, wherein the display control functioncontrols displaying the information on the difference concerning theobject type specified from the operation unit.
 10. A digital plateinspection method comprising: a display step of causing a display todisplay page content of each of a first page and a second page expressedin a page description language; and using a processor to perform: adifference detection step of detecting a difference between an objectincluded in the first page and an object included in the second page byanalyzing an object structure in page description data of each of thefirst page and the second page and by comparing the first page and thesecond page which are each in a state of an object of the pagedescription data; and a display control step of controlling the displayto display information on the difference detected by the differencedetection unit, wherein in the difference detection step, the processorfurther performs an object comparison processing step to comparesimultaneously the objects for each of plural object types in units ofobjects which belong to the same object type, the objects beingclassified into the plural object types used for the page descriptionlanguage; the method further comprising accepting a user operationspecifying an object type, of the plural object types, on which theinformation on the difference is to be displayed, wherein the displaycontrol step displays the information on the difference concerning theobject type specified from the accepting the user operation.